As thousands of repeat customers will tell you, ThermaCELL is unbeatable at repelling mosquitoes, black flies, and no-see-ums. Tests by the US Army have found ThermaCELL to be up to 98% effective within a 15 ft. x 15 ft. area. The ThermaCELL Mosquito Repellent Patio Lantern produces a soft glow while providing protection against mosquitoes, making it ideal for use on your patio or campground. This Mission-inspired lantern is aesthetically pleasing with a wrought iron look for classic appeal. It provides safe, effective lighting without messy candle wax. ThermaCELL provides a great alternative to DEET- there is no more need for messy, smelly lotions or sprays. Each unit comes with 12 hours of protection. Additional refills are available for purchase, either in a single refill pack (good for 12 hours) or a refill value pack (good for 48 hours). This product is registered by the EPA.